2 Copyright (C) 2000, 2001, 2003, 2004, 2007, 2008, 2009
3 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation; either version 3, or (at your option) any
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; see the file COPYING3. If not see
17 <http://www.gnu.org/licenses/>. */
19 #ifndef LIBCPP_SYMTAB_H
20 #define LIBCPP_SYMTAB_H
24 #define GTY(x) /* nothing */
27 /* This is what each hash table entry points to. It may be embedded
28 deeply within another object. */
29 typedef struct ht_identifier ht_identifier;
30 struct GTY(()) ht_identifier {
31 const unsigned char *str;
33 unsigned int hash_value;
36 #define HT_LEN(NODE) ((NODE)->len)
37 #define HT_STR(NODE) ((NODE)->str)
39 typedef struct ht hash_table;
40 typedef struct ht_identifier *hashnode;
42 enum ht_lookup_option {HT_NO_INSERT = 0, HT_ALLOC};
44 /* An identifier hash table for cpplib and the front ends. */
47 /* Identifiers are allocated from here. */
51 /* Call back, allocate a node. */
52 hashnode (*alloc_node) (hash_table *);
53 /* Call back, allocate something that hangs off a node like a cpp_macro.
54 NULL means use the usual allocator. */
55 void * (*alloc_subobject) (size_t);
57 unsigned int nslots; /* Total slots in the entries array. */
58 unsigned int nelements; /* Number of live elements. */
60 /* Link to reader, if any. For the benefit of cpplib. */
61 struct cpp_reader *pfile;
63 /* Table usage statistics. */
64 unsigned int searches;
65 unsigned int collisions;
67 /* Should 'entries' be freed when it is no longer needed? */
71 /* Initialize the hashtable with 2 ^ order entries. */
72 extern hash_table *ht_create (unsigned int order);
74 /* Frees all memory associated with a hash table. */
75 extern void ht_destroy (hash_table *);
77 extern hashnode ht_lookup (hash_table *, const unsigned char *,
78 size_t, enum ht_lookup_option);
79 extern hashnode ht_lookup_with_hash (hash_table *, const unsigned char *,
81 enum ht_lookup_option);
82 #define HT_HASHSTEP(r, c) ((r) * 67 + ((c) - 113));
83 #define HT_HASHFINISH(r, len) ((r) + (len))
85 /* For all nodes in TABLE, make a callback. The callback takes
86 TABLE->PFILE, the node, and a PTR, and the callback sequence stops
87 if the callback returns zero. */
88 typedef int (*ht_cb) (struct cpp_reader *, hashnode, const void *);
89 extern void ht_forall (hash_table *, ht_cb, const void *);
91 /* For all nodes in TABLE, call the callback. If the callback returns
92 a nonzero value, the node is removed from the table. */
93 extern void ht_purge (hash_table *, ht_cb, const void *);
95 /* Restore the hash table. */
96 extern void ht_load (hash_table *ht, hashnode *entries,
97 unsigned int nslots, unsigned int nelements, bool own);
99 /* Dump allocation statistics to stderr. */
100 extern void ht_dump_statistics (hash_table *);
102 #endif /* LIBCPP_SYMTAB_H */